Norv Turner was hired Monday as San Diego Chargers head coach in a departure that left the 49ers searching for a third offensive coordinator in three seasons.

But even as Coach Mike Nolan commenced the search for a replacement, he reiterated through a team spokesman that he intends to retain the system Turner installed when he joined the 49ers last year.

That would spare quarterback Alex Smith and the rest of the offense from having to learn a new scheme after showing significant progress under Turner.

Still, the loss of Turner dealt a blow to the continuity the 49ers strove for in hopes it would translate to even greater strides next season for Smith, whose passer rating nearly doubled to 74.8 last year after a disastrous
Less than two weeks ago, it appeared Turner would be back for another season after Cowboys owner Jerry Jones passed him over for the Dallas head-coaching job in favor of Wade Phillips, the Chargers’ former defensive coordinator. Turner was rewarded with a new deal by the 49ers, who gave him a raise and extended his contract through 2009.

But last week, Chargers President Dean Spanos fired Marty Schottenheimer as coach. He cited Schottenheimer’s conflict with General Manager A.J. Smith and a recent exodus of assistant coaches, including Phillips and Greg Manusky, the 49ers’ new defensive coordinator.

Turner had previous ties to San Diego, having served as the Chargers’ offensive coordinator in 2001, when he helped to develop then-rookies LaDainian Tomlinson and Drew Brees. Turner and assistant 49ers head coach Mike Singletary were among six candidates Chargers officials interviewed for the job.

An NFL head coach for the third time – he went 58-82-1 in stints with Washington and the Raiders – Turner takes over a Chargers team that sent 11 players to the Pro Bowl after going a league-best 14-2 last season. Heavily favored to reach the Super Bowl, San Diego lost to New England in the second round of the playoffs.

“This is a great opportunity for Norv,” Nolan said in a statement released by the 49ers.

Turner, 54, let Nolan know he was leaving in a phone call several hours before his introductory news conference in San Diego.

“Expectations for this team obviously are high,” Turner said in San Diego. “I couldn’t be more excited to coach here. The players and the chance to win a championship are what attracted me to this job.”

Nolan’s search for Turner’s replacement will include gathering input from his players and consideration of all five offensive assistants remaining on the 49ers staff.

Wide-receivers coach Jerry Sullivan is the only one among them with experience as an NFL offensive coordinator, having served in that role in Arizona in 2003.

Quarterbacks coach Jim Hostler and tight-ends coach Pete Hoener served as college offensive coordinators. Offensive-line coach George Warhop spent two seasons as offensive coordinator with London of NFL Europe. Running-backs coach Bishop Harris was a head coach at North Carolina Central (1991-92).

All have extensive experience in Turner’s offensive system, which would address one of Nolan’s key concerns.

Nolan also indicated he will consider candidates outside the organization. One possibility could be Cincinnati quarterbacks coach Ken Zampese. The 49ers would need to get permission from the Bengals to interview Zampese, whose father, Ernie, was an NFL offensive coordinator and an early mentor of Turner.

“I said last year when we went through a similar situation that I view it as an opportunity to get better,” said Nolan, who brought in Turner after Mike McCarthy left the 49ers to become Green Bay’s head coach. “I have confidence in the structure of our organization and our ability to attract and recruit the best for our team.”

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